Injuries that cause damage to cartilage, especially cartilage in the knee, are quite common. The cartilage-damaging injuries can occur during sports, at work, or as a result of accidents such as falls or automobile accidents. Cartilage in the knee joint, such as the meniscus, serves the purpose of both supporting the joint and providing a sliding surface that is engaged by the ends of the bones in the knee. Damage to cartilage in the knee can result in knee instability and pain, and over the long term, may result in deterioration of the articulating surfaces of the bones, which may cause arthritis. Medical science has progressed in the treatment of damaged cartilaginous tissue including that in the meniscus. At one time it was believed that cartilaginous tissue could not heal because of the minimal blood supply that typically is associated with cartilage. A typical surgical procedure involved cutting out all or most of damaged cartilage in order to restore some limited joint function. Presently, it is known that the body can heal damaged cartilaginous tissue. Typically, cartilaginous tissue that is damaged or torn may be approximated allowing the damaged tissue to heal. Various devices and methods are available for repairing damaged cartilaginous tissue. The most basic device is a conventional surgical suture. Using a surgical needle and suture, the damage to the cartilaginous tissue, typically a tear, is approximated and maintained by the suture in a fixed position to effect a repair. Typically, suturing is a procedure utilized in an open surgical procedure.
It is known in this art to use minimally invasive procedures in the knee to repair soft tissue, including cartilage. Various tissue fixation devices and application tools have been developed to allow for arthroscopic repair procedures. One example of a meniscal repair device is a meniscal screw that is inserted across a tear in cartilage to bring or approximate the edges of the tear together. Meniscal screws are disclosed in U.S. Pat. Nos. 5,569,252, 5,730,744 and 6,468,277, which are incorporated by reference. Another type of meniscal repair device is an “H-shaped” fastener. Such fasteners are disclosed in U.S. Pat. Nos. 5,085,661, 5,320,633, 5,467,786, 5,470,337, 5,601,571 and 5,941,439, which are incorporated by reference. A combination suture and back anchor device for repairing a tear in a meniscus is disclosed in U.S. Pat. Nos. 4,994,074, 6,047,826, 6,306,159, 6,319,271 and 6,432,123 which are incorporated by reference.
Although such fasteners are useful in arthroscopic tissue repair procedures, there is a constant need in this art for novel and improved devices and methods for repairing soft tissue such as cartilage. It is desirable when repairing a tear in soft tissue in a joint, such as cartilaginous tissue, to leave behind the least amount of mass required in the implant to do the repair. It is known that suture will typically provide the least mass for an implant. However, it is known that it is difficult and requires significant precautions to emplace suture in cartilaginous tissue in an arthroscopic procedure requiring the passage of needles entirely through the joint capsule and out a secondary posterior incision, then tying the ends together by hand. The risks associated with such a procedure include possibly damaging neurovascular structures by needle punctures or nicks, or by inadvertently looping suture around them.
Accordingly, there is a need in this art for novel stitching devices and methods for repairing soft tissue that are useful in minimally invasive surgical procedures, particularly arthroscopic surgical repair procedures.